Exemplary embodiments of the present invention relate to a wheel alignment apparatus using a motor-driven power steering (MDPS) and a control method thereof, and more particularly, to a wheel alignment apparatus using an MDPS and a control method thereof, which detects a steering angle and aligns a wheel with the center by controlling an MDPS motor through a motor angular velocity and a motor current, after a vehicle having the MDPS mounted therein is parked.
Examples of an electronic control unit (ECU) which is generally applied to a vehicle may include an MDPS which reduces a manipulation force of a steering wheel according to the speed of the vehicle such that a steering manipulation may be softly and quickly performed.
The MDPS is operated as follows. First, the ECU receives input signals from a steering angle sensor, a torque sensor, a vehicle speed sensor, and an engine RPM sensor, calculates a current value corresponding to a torque value, and supplies the calculated current value to an MDPS motor, when the steering wheel is steered. Then, the MDPS motor generates a power assist force through rotations and deceleration so as to rotate a universal joint, and operates a pinion and rack using the rotational power of the universal joint such that the steering wheel is steered through a tie rod. Accordingly, the MDPS has steering performance and feeling which are improved more than a hydraulic power steering.
In this connection, Korean Patent Laid-open Publication No. 10-2010-0007321 discloses a wheel alignment apparatus of a motor-driven power steering vehicle.
Although the above-described MDPS is used, a driver may feel inconvenient when performing center alignment of the steering wheel after parking the vehicle. When the driver starts the vehicle in a state where the center alignment is not carried out, a vehicle collision is likely to occur.